You can use pie crust dough instead of crescent dough. The cooking time may be longer.
Don't want to make individual muffin tin cups? Place half the dough in an 8x8 pan. Add chicken mixture and then top with the other half the dough. Bake as usual. The cooking time will be longer.
A sprinkle of poultry seasoning in the mix can ramp up the flavor even more.
Use leftover turkey instead of chicken.
No need for an egg wash, the chicken pot pie with crescent rolls have enough butter in the pastry that they will be flaky and golden brown.
Warm up the frozen vegetables before adding to the mixture for more even cooking.
I like to add small diced potatoes or frozen peas to my mixture.